EDITORIAL
Food safety is a priority
worldwide as it is
critically
important
to everyone involved
in food production to
maintain the trust of the
consumer. Microbiology
testing
for
food
pathogens is performed
by the food processors
and manufacturers to ensure a safe,
quality product.
As the pressure for more pathogen
testing increases, food companies
look for more cost-effective testing
solutions
to
meet
budgetary
requirements. As a food processor,
choosing the best pathogen detection
method can be a very difficult
decision. The method should have a
meaningful impact on the total costin-use for your food safety program
but
most
importantly,
provide
maximum assurance of reliability in
your test results.
Romer
Labs’
RapidChek®
and
®
RapidChek
SELECT™
pathogen
detection systems were developed
to deliver the required time-toresult and accuracy while also
providing documented cost savings,
faster product release, ease-of-use,
batch size scalability and 3rd party
certifications.
Tim Lawruk

Trends and breakthroughs in food
pathogen analysis
The global food microbiology testing market is estimated
at $ 3 billion with almost 1 billion tests performed annually.
The analysis of food pathogen targets such as Salmonella,
Listeria, E.coli O157 and Campylobacter account for $ 1.4
billion or around 224 million tests of the food microbiology
market which is a 30 % increase since 2008. While the EU
is using 50 % traditional methods and 50 % rapid methods,
the US primarily uses rapid methods including antibody-based
lateral flow devices and ELISA plates and molecular methods
such as PCR. Asia and the rest of the world mainly continue
to use traditional cultural plate methods (Strategic Consulting
2013).
Globally, 50 % of the tests performed are conducted in
finished products, 40 % on in-process or environmental
testing. In North America the focus is more on environmental
and in-process testing, whereas Europe and Asia are mainly
focusing on finished product testing with little environmental
monitoring.
After a decade of solid but quiet growth, the microbiology
testing requirements of the food processing industry-

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especially in pathogen testing-have been thrust
into the public spotlight again, driving healthy
growth in food diagnostic testing. Overall market
value growth has averaged 13.0 % over the past
three years and pathogen testing market value has
averaged 18.0 % during the same time.
While food companies continue to make investments
in their overall food safety programs, new
regulations, outbreaks, and public concern drive
even more pathogen-specific testing. Pathogens
are everyone’s focus. As a result, new diagnostic
technologies and new players are entering the
market, and the business landscape is continuing
to change through acquisitions, partnerships, and
new product offerings.
Rapid Methods for Food Pathogens
When the science of microbiology was in its early
stages of development, scientists used liquid
culture media for the cultivation of microorganisms.
Agar revolutionized the science of microbiology
as it made what had been a difficult task of
separating and culturing microorganisms on solid
surfaces a routine procedure. Interestingly, over
100 years later, all microbiology laboratories, in
every industry sector, continue to use agar as the
most important and widely accepted material for
growing microorganisms today. These traditional
cultural microbiology methods typically require
trained microbiologists to interpret results and call
for 48 – 72 hours enrichment incubations.
Current rapid method technologies can detect the
presence of food pathogens by various techniques
dependent on the specific technology and
instrumentation employed. These methods require
that the sample still be enriched in a liquid media
to grow the target pathogen to a detectable level.
The primary rapid microbiology detection platforms
used in the food industry today are antibody-based
platforms such as lateral flow devices or ELISAbased methods and molecular-based platforms
such as PCR methods. Laboratories chose these
rapid methods over the traditional cultural methods
because they provide a much faster time-to-result
(8 – 24 hrs), are easier to use and interpret results
and provide economical high throughput screening.

Food Industry Perspective on Rapid Methods
for Pathogens
The food industry must use pathogen detection
methods that are reliable and consistent in their
performance. Currently, multiple rapid method
platforms are in use including immunological and

genetic platforms. The data generated by these
methods must also be defendable with regulatory
bodies. A fast time-to-result is important, but
cannot compromise the accuracy of the methods.
Rapid methods are a very good screening tool, as
they are cost effective and deliver results faster
than traditional cultural methods. However, “fit for
use” verification of these methods is absolutely
necessary prior to adopting a specific technology.
Food testing laboratories typically work with rapid
method developer to determine how a protocol
is validated for the particular sample type and
application and whether field performance studies
are required to verify method performance.
One hurdle for the food industry laboratory is
that more structure is needed for these validation
studies. Each rapid test kit manufacturer designs
validation studies differently and there is no uniform
standard which makes it difficult to interpret data,
compare methods and apply them to real-world
applications. An on-line, up-to-date summary of
a method’s validation data and product claims as
well as in-house validations and special studies
would also help laboratories compare rapid test
methods for use in specific applications.
Time-to-result is the test method feature that most
laboratories would like to improve upon; however,
it is important to maintain performance and ease
of use characteristics.
Regulatory Perspective on Rapid Methods for
Pathogens
From a general regulatory view, results generated
from rapid food pathogen method must be
unequivocal in nature (no misunderstanding,
or misinterpretation). For example, real-time
detection methods are favorable for the USDA FSIS
with dependable outcomes that are very repeatable.
These agencies are also interested in real-time
systems that are fast, accurate, and practical to
implement. Many regulatory agencies are looking
to develop guidelines for method validation
protocols and databases of validated methods to
aid industry in selecting the appropriate methods.
A future area of focus for the US-based regulatory
agencies is whole genome sequencing. Whole
genome sequencing offers great opportunities for
outbreak investigations, but also risk assessment.
These technologies and their applications are
currently developed and studied at the academic
levels and some interactions and case studies have
been initiated with the food industry in order to
demonstrate their input in regards of food safety
issues and risk management.

www.romerlabs.com · Romer Labs® Spotlights Vol. 28

Future Trends in Food Pathogen Analysis
Sample preparation & workflow
Because food pathogen detection methods
still require a lengthy enrichment step, sample
preparation and method workflow are key areas
of improvement for rapid pathogen methods. Time
to result remains the key issue and improved
enrichment or non-enrichment methods with good
workflow and data management capabilities are
required. Possible improvements in the sample
enrichment include fewer broths or more universal
broths for multiple pathogens, reduced enrichment
volumes and fewer hands-on steps. Universal
sampling, enrichment broths, and workflow will
streamline testing in laboratories where multiple
pathogens are analyzed. A database listing all
the methods for sample preparation is desirable
given the high diversity of matrices involved for
pathogen testing.
Detection of Genes, Species and Serogroups
Over the past three years, scientists at the U.S.
Food and Drug Administration have conducted whole
genome sequencing on hundreds of foodborne
pathogens to get a detailed map of their DNA. The
initiative, titled “The 100K Genome Project,” is
a private-public collaboration between FDA, the
University of California Davis and Agilent, hopes to
expand that figure to 100,000. By developing this
new database, regulators hope to help health officials
cut down on the time it takes to identify the source
of an outbreak. The debate over the value of genome
sequencing versus serotyping is still ongoing. In
reality, both detection technologies provide valuable
information.
For gene detection using molecular rapid methods,
the main challenges are to find the right combination
of targets as well as understanding the virulence of
the genes that are being targeted. Trying to connect
the gene targets to disease virulence, will require
the regulations to evolve in regards to detection
technology and their reliability.

overall effectiveness of the microbiological controls
that are in place. Listeria species is used as an
indicator of contamination control in refrigerated,
wet-processing environments typically found in readyto-eat meat processing plants. Salmonella species is
used as an indicator of contamination control in lowmoisture processing environments typically found in
other types of ready-to-eat food processing plants.
However, there is limited data on the effectiveness
of some environmental monitoring programs and its
prediction of risk and control will depends upon the
specific product/process/plant under consideration.
Emerging Pathogens
Currently, food pathogen targets such as Salmonella,
Listeria, E.coli O157 account for over 93 % of the 224
million pathogen tests performed globally. However,
there are new emerging threats that have the
attention of the food industry, test manufacturers and
regulators. These threats include: foodborne viruses
such as Norovirus and hepatitis A and E, parasites
such as Cyclospora and Giarda, Staphylococcus
aureus, and non-top 6 STEC such as E. coli O104.
There is an increasing concern in new and emerging
pathogens that are antibiotic resistant. Of particular
concern for food are strains of Salmonella that are
resistant to antimicrobial agents and have become a
worldwide health problem. Multi-drug resistant (MDR)
Salmonella continues to pose a public health threat,
particularly as resistance spreads across classes of
drugs, necessitates the use of more expensive drugs,
makes treatment less effective, and, in worse-case
scenarios, leaves infections untreatable. Couple
the MDR strains of bacteria with the unknown risk
that pathogens from developing countries might
be reintroduced to the developed world through
importation, will necessitate that the global food
supply chain needs increased monitoring.

There is an increasing amount of environmental
monitoring for the preemptive control of food
pathogens in the food processing environment.
Environmental monitoring is an ongoing process of
sampling and testing that measures the effectiveness
of the contamination control measures, such as
sanitation practices, in a plant. An effective monitoring
program is a critical component to measuring the

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ABOUT THE AUTHOR
Name

Position

Tim Lawruk
Sr. Director of Sales & Marketing since 2012

Education Bachelor of Science in Chemistry, minor in Business Administration from